A “duty cycle” in digital communication systems refers to the pulse/pause or on/off ratio in an electrical signal. In particular, the duty cycle indicates the percentage in which there is a high level in a signal. Ideally, the duty cycle is 50% or 0.5.
The duty cycle is an important characteristic quantity for dynamic interface signals in digital communication systems. Dynamic interface signals are, in particular, input and output signals for digital communication components. For the duty cycle, there are generally very restrictive specifications in order to ensure that individual components work in an overall system. The greater the number of components, the more it is necessary to restrict the specification. Observing this specification under all constraints, such as temperature, supply voltage and manufacturing tolerances, is often a problem.
When there are a large number of system components in a signal chain, it is known practice to incorporate, as a rule, a retiming stage (clock recovery) in order to regenerate the signal again in respect of its requirements. In this context, the signal is refreshed in terms of jitter and duty cycle, in particular. However, a drawback of such retiming stages is that they require considerable complexity in terms of additional system components.
There is generally a need for circuit arrangements which allow simple and effective regulation of a parameter of an electrical signal. In particular, there is a need for circuit arrangements for regulating the duty cycle of an electrical signal.